The present invention relates in general to recoil systems for guns, and in particular to a new and useful recuperator system which functions to break the recoil of a gun and return it to battery, and which is lightweight, efficient and reliable.
Systems for braking the recoil of a gun must be at least reliable enough to consistently return the gun to battery, that is to its firing position.
Previously and on present tanks, such as the M-60 and M-1, this function has been performed by a concentric hydrospring mechanism which is neither lightweight, efficient nor reliable. This mechanism brakes the recoiling parts by throttling oil through an orifice in a large concentric cylinder centered around the gun tube. A mechanical spring fitted in the same cylinder is compressed by the displacement of recoil and therefore provides the restoring force at the end of the recoil stroke.
The concentric hydrospring has proven to be unsatisfactory for several reasons.
From experience with the M-60 tank system, the concentric hydrospring arrangement is susceptible to leaks of the recoil fluid which, if in excess, results in a major failure of the gun system.
The mechanical spring is slow to respond to the quick loading which it is subjected to and often breaks and thus fails to return the gun to battery. The large diameter of the hydrospring makes it difficult to control the size of the orifice and therefore the force transmitted to the trunnions of the gun. The mechanism has many parts and represents a sizable portion of the weight of the cannon system (1,700 lbs. on the M-60). Also, if the mechanism does fail, it is a major operation to place any or all of it. This cannot be done in the field.
Proposed future gun recoil systems include use of one or more smaller diameter Schneider type recoil brake cylinders and a separate recuperator cylinder for restoring the gun to battery. These cylinders are mounted on the gun/breach on one end, and the trunnions on the other.
The separate Schneider system offers solutions to most, if not all of the problems experienced with concentric mechanisms. It is smaller, lighter and has fewer parts. It has proven reliable on such gun systems as the Soviet T-55 and T-62. Should it need replacement, it requires an ordinary wrench and a matter of a few minutes to replace the entire unit.
The Schneider system could be further improved, however, if the recoil brake and recuperator could combine to eliminate the need to have two different replacement cylinders for spare parts. Present recuperator designs also involve a fairly complex transfer of oil volume to compress a gas volume by a specific amount, to provide the required restoring force for counter-recoil movement of the gun.